2pcs B234-3171 B2343171 B234-3181 for af1350 MP1100 MP1350 MP9000 Pro 1107 1357 907 Developer Unit Entrance Seal The B234-3171 B2343171 B234-3181 Developer Unit Entrance Seal is designed to maintain proper function in the drive system of compatible printers including af1350, MP1100, MP1350, MP9000, Pro 1107, 1357, and 907 models.This seal fits securely between the developer unit and the printer to help prevent toner leakage and protect internal components during.Constructed for , it supports consistent function under regular use.The seal is engineered for straightforward installation and serves as a functional replacement part that integrates into existing printer systems without requiring tools or expertise.